NIST Alcatel-Lucent Nokia Telcordia Technologies Inc. InterDigital Communications This document describes a mobility services framework design (MSFD) for the IEEE 802.21 Media Independent Handover (MIH) protocol that addresses identified issues associated with the transport of MIH messages. The document also describes mechanisms for Mobility Services (MoS) discovery and transport-layer mechanisms for the reliable delivery of MIH messages. This document does not provide mechanisms for securing the communication between a mobile node (MN) and the Mobility Server. Instead, it is assumed that either lower-layer (e.g., link-layer) security mechanisms or overall system-specific proprietary security solutions are used. [STANDARDS-TRACK]